@article{Fan2023, 
author = {Lili Fan and Xiaofei Wei and Xuting Li and Zhanning Liu and Mengfei Li and Shuo Liu and Zixi Kang and Fangna Dai and Xiaoqing Lu and Daofeng Sun},
title = {Phosphorus-doped iron-nitrogen-carbon catalyst with penta-coordinated single atom sites for efficient oxygen reduction},
year = {2023},
journal = {Nano Research},
volume = {16},
number = {2},
pages = {1810-1819},
keywords = {oxygen reduction reaction, Fe-N-C, Fe-N4, penta-coordination, P-doping},
url = {https://www.sciopen.com/article/10.1007/s12274-022-4939-5},
doi = {10.1007/s12274-022-4939-5},
abstract = {Single-atomic Fe-N4 is the well-acknowledged active site in iron-nitrogen-carbon (Fe-N-C) material for oxygen reduction reaction (ORR). The adjusting of the electronic distribution of Fe-N4 is promising for further enhancing the performance of the Fe-N-C catalyst. Herein, a phosphorus (P)-doped Fe-N-C catalyst with penta-coordinated single atom sites (FeNPC) is reported for efficient oxygen reduction. Fe K-edge X-ray absorption spectroscopy (XAS) verifies the coordination environment of single Fe atom, while density functional theory (DFT) calculations reveal that the penta-coordination and neighboring doped P atoms can simultaneously change the electronic distribution of Fe-N4 and its adsorption strength of key intermediates, reducing the reaction-free energy of the potential-limiting step. Electrochemical tests validate the remarkable intrinsic ORR activity of FeNPC in alkaline media (a half-wave potential (E1/2) of 0.904 V vs. reversible hydrogen electrode (RHE) and limited current density (JL) of 6.23 mA·cm−2) and an enhanced ORR performance in neutral (E1/2 = 0.751 V, JL = 5.27 mA·cm−2) and acidic media (E1/2 = 0.735 V, JL = 5.82 mA·cm−2) with excellent stability, highlighting the benefits of optimizing the local environment of single-atomic Fe-N4.}
}